The currency bounced back Friday, but analysts said further falls were likely if Ukraine fails to agree to a bailout with Russia or the European Union.

"In the absence of a sizeable assistance package from either Russia or the EU, Ukraine's low level of foreign exchange reserves means that a disorderly devaluation, in which the hryvnia overshoots on the downside, remains a real threat," wrote emerging markets economist Neil Shearing from Capital Economics, estimating the currency could fall by another 20%.

Thousands of anti-government demonstrators have packed Kiev's Independence Square since then, underscoring tensions in a country split between pro-European regions in the west and a more Russia-oriented east.

Russia bought $3 billion in Ukrainian government bonds in December as part of an aid package worth about $15 billion -- and also offered Ukraine big discounts on natural gas. But Moscow now appears unwilling to hand over any more money because of the political backlash.

A weaker currency and dwindling reserves are making it harder for Ukraine to pay its debts, including bills for Russian gas imports.